Driving connection for surgical instruments



Oct. 20, 1942. s. 1 FISHER 2,299,268

` DRIVING CONNECTION FOR SURGICAL INSTRUMENTS original Filed June 11, lass ummm 'IIM*Illllllllllllllllll `HIIHMNIIII Patented Oct. 20, 1942 DRIVING CONNECTION FOR SURGICAL INSTRUMENTS Samuel Lloyd Fisher, Brooklyn, N. Y.

Original application June 11, 1938, Serial No. 213,115. Divided and this application May 14, 1941, Serial No. A393,316

4 Claims. (Cl. 12S-317) This invention relates to surgical instruments in Vgeneral and more especially to devices used in the medical profession in the treatment of bone fractures and the like and constitutes a division in part of application Serial No. 213,115, led June 11, 1938, issued as Letters Patent No. 2,244,683 on June 10, 1941.

It is an object of the present invention to provide an improved combination shell and motor which can be operatively connected with a high speed surgical drill, saw or the like or with a low speed router screw or the like without interfering with any of the attributes essential to a surgical instrument that can be readily sterilized and satisfactorily retained in its sterilized condition.

These and other features, capabilities and advantages of the invention will appear from the subjoined detail description of one specific embodiment thereof illustrated in the accompanying drawing in which:

Fig. 1 is a longitudinal section of an auxiliary shell with a side elevation of a reduction associated therewith and a screw holding attachment partly in section in operative association with the main shell illustrated in Fig. 1;

Fig. 2 is an elevation showing two bone portions connected by a screw and the screw holder after having been removed from the screw;

Fig. 3 is a section on the line of Fig. 2;

Fig. 4 is a section on the line 2|2 of Fig. 1;

Fig. 5 is a section of the auxiliary shell and associated parts on the line |3-I3 of Fig. 4, the line l3|3 being inclined relative to the sec- Ation of Fig. 1.

For high speed work when a Kirschner wire drill is operated then preferably the extension 39 of the shell I has connected thereto an intermediate connecting device such as shown in my co-pending application for patent Ser. No. 393,315, filed May 14, 1941.

The present invention aims to reduce the parts in a surgeons kit to a minimum and for this reason shows a reducing element which may be attached to the shell for operating, as an instance, a slow turning binding screw for binding' two bone elements such as the elements ||5 and H6 to one another. In the present instance, there is shown as attached to the reducing element the screw ||1 which has a tapered en-d H8 and an angular head H9 to be gripped by a tool holder having a spring finger |2| frictionally to engage one side of the angular head H9. The tool holder |20 has a spindle |22 which may able means, such for instance as the intermediate element 223 having a chamber for the spindle |22 provided with recesses to receive pins on the shaft |23, and the locking nut |24provided to secure locking jaws to the spindle |22, such as the locking jaws 95, in which case the intermediate element 223 is journaled in the bearing |25 supported by the end wall |26 of the auxiliary shell |21, while the shaft |23 as part of the intermediate element 223 is preferably journaled, as shown, in the partitions |28 and |29.

On the shaft |23, there is fixed in the present instance, the gear |30 in mesh with the small gear |31 on the shaft |32, which shaft |32 is journaled in the partitions |28 and |29. On the shaft |32, there is fixed the large gear |33 in mesh with the small gear |34 on the shaft |35 also journaled in the partitions |28 and |29. On the shaft |35,.there is fixed the large gear |36 in mesh with the small gear |31 xed on the shaft |38 also journaled in the partitions 28 and |29.

On a portion of the shaft |38 extending between the partition |28 and the end wall |26,

F there is fixed the large gear |39 in mesh with the small gear |40 xed on the shaft 4| journaled in the block |42 and the partition |28. The inner end of the shaft |4| is provided with pins |43 to receive the slots |44 formed in the tubular portion of the intermediate -connecting member |45 provided with another tubular portion in which are formed the slots |46 to receive pins on the shaft of the motor extending into the cylindrical extension 39 on the shell The shell |21 is provided with a bayonet slot |41 to receive the pin |48 on the shell and thus lock it in position, the open end of the shell |21 being cammed into position by the rounded end of the shell the connecting member |45 being iioatable to facilitate connecting engagement with pins on the shaft of the motor.

The screw ||1 is formed to facilitate movement of the same in a predetermined straight line. As an instance, the end H8 is provided with a centrally located point |53 from which the screw tapers outwardly into the tapered portion 8 to the main body portion with a very gradual incline to the thread approximating fortyve degrees to the axis of the screw. 'I'his screw |I1, as shown in Fig. 2, is intended to be left in the bone until the fractured pieces have knit and in some cases is left there permanently.

In View of the foregoing, after the drill attach- 55 ment, shown in Fig. 1, has turned the screw ||1 be connected to the driven shaft |23 by any suitinto place, the spring lip |2| comes into play, it

then only being necessary to frictionally slip the spindle |22 from the screw head H9 and leave the screw ll'l in the bone. In some cases, it may be desirable to remove the screw Hl after the bone portions have become knit. Then it will only be necessary to make a small incision to expose the head IIS and then frictionally slip the spindle v|22 into place, set the motor for reverse movement and the screw will be rotated in the reverse direction and removed.

The reduction unit used when a screw, such 'as the screw Ill, is to be secured in place or removed has already been explained, the reduction in revolutions per minute! being approximately from sixteen thousand It. P. M. to .one hundred R. P. M. which is reduced to eighty R. P. M. under load whereby any boring or drilling action will be eectively avoided and the screw merely cut itself into a locking position in the bone. Obviously, since the screw Ill is intended to be left in the bonetissue, it is desirable to produce these screws from non-oxidizing metal, such as stainless steel or the like.

. When the wire drill is used, it is particularly desirous to have the wire 91 drill through a bone in a perfectly straight path since experience .has taught that in such cases the accompanying pain Ito the patient when traction is made may be reduced to a minimum if not entirely eliminated. With the present guiding elements IDI, ID3 and ISS and the combination motor holder and instrument attachment, the operating surgeon is merely called upon to hold the motor steady after making contact. After the wire 91 has so been drilled through the bone, the ordinary Kirschner horse-shoe clamp may be used to maintain the wire stretched in a straight line and then the weight attached to the horse-shoe clamp in the usual way.

Before the horse-shoe Yclamp aforesaid is attached in order to remove a wire 91 from the drilling attachment, in some instances, the same is cut off leaving a small portion in the drilling attachment. In other cases, the guiding elements lill, lllS and 'W5 are moved away from the shell l to clear the ring 8l whereupon the Vprojections 81%, 8 5 and 3S are engaged and turned. To prevent "the wire 91 from turning during this procedure, the motor is rst'shut off and then the stop pin 45 engaged and pressed to enter one of the slots 42 whereupon the ring '89 can Ywith facility b e turned, and thereupon the guiding elements lill, HB3, li and wire drill attachment removed whereupon the clamping nut '9d Vcan be turned to release the jaws 95 or else the nut 94 turned to release .the jaws 95 .before the ring Y8l is turned.

It is obvious that various changes and modications may be made to the details of construction without departing from the general spirit of the invention as set forth in the appended claims.

I claim:

1. The combination of an electric motor having a shaft with pins extending radially therefrom, a main shell having a main cylindrical outer periphery terminating in a rounded end ,with a shaft opening in the center of 'said rounded end registering with said shaft and a pin extending radiallyY outward from said cylindrical outer periphery adjacent to said rounded end, and a removable unit including an auxiliary shell having a cylindrical open end conforming to the cylindrical periphery of said main shell to receiveV said rounded end and engage the cylindrical outer periphery of said main shell, said auxiliary shell having a bayonet slot to receive said pin removably to connect said auxiliary shell to said main shell, said removable unit containing a reduction gearing including a fixed shaft having radially extending pins, a connecting shaft having tubular, portions at its free ends with radially extending slots therein to receive the pins of said motor shaft and fixed shaft respectively and floatable to facilitate connecting .engagement with said motor shaft when the Lopen cylindrical end of said auxiliary shell is cammed on to the rounded end of said main shell, a driven shaft operatively connected to said reduction gearing, there being an opening kin the lend of said auxiliary shell, and a spindle for a surgical instrument extending through said opening and operatively connected to said driven shaft.

2. The combination .of an electric motor having a shaft, a main shell having a main cylindrical outer periphery terminating in a rounded en d with a shaft .opening in the center of said rounded end registering with said Vshaft and a pin extending radially .outward from said cylindrical outer periphery adjacent to said rounded end, and a removable unit including Yan auxiliary shell having a cylindrical open end conforming to the cylindrical periphery of said main shell -to receive said rounded end and engage the cylindrical outer periphery of said main shell, said auxiliary shell having a bayonet slot to receive said pin removably to connect said auxiliary shell to said main shell, said removable unit containing a reduction gearing including a connecting shaft movable to facilitate connecting engagement with -said motor shaft when the open cylindrical end of said auxiliary shell is cammed o n to the rounded end of said main shell, a bearing in the end wall of said auxiliary shell, .an

intermediate rotatable element journaled in said bearing, a driven shaft operatively connected to said reduction gearing and extending into and fixed to rotate with said intermediate rotatable element, a spindle for a surgical instrument extending into said 'intermediate rotatable element and operatively connected to rotate with said driven shaft. and a lock nut screw threadedly connected to the outwardly projecting end of said intermediate element and clutching said spindle to said intermediate element against axial movement relative to said driven shaft but permitting rotatable movement.

3. The combination of an electric motor having a shaft, ra main shell having a shaft opening registering with said shaft, and aV removable unit including an auxiliary shell connected to said main shell, said removable unit .containing a reduction gearing including a .connecting shaft, a bearing in the end wall of said auxiliary shell, an intermediate rotatable element journaled in said bearing and having a cylindrical portion extending outwardly from said auxiliary shell with external screwrthreads thereon, a driven shaft fixed to rotate with said rotatable element having radially extending pins on its free end and operatively connected to Vsaid reduction gearing, a spindle for a surgical instrument extending in to Said bearing having radial slots on its inner end to engage the pins on said driven shaft to effect a rotatable engagement therewith, and a lock nut screw threadedly connected to lthe threaded portion of said intermediatev .element and clamping said spindle to anchor it against to receive the pins of said driven shaft to effect a rotatable movement therewith, a lock nut clamping said spindle to said intermediate element to anchor it against axial movement relative to said drive shaft b-ut permitting rotatable movement therewith, a tool holder on the end of said spindle including an angular recess and a spring tongue therein and a screw having an angular head frictionally held in said angular 10 recess by said spring tongue.

SAMUEL LLOYD FISHER. 

